Milan Pavkov scored twice in seven first-half minutes to hand Red Star their first Champions League victory in 26 years.
Liverpool still lead Group C but could fall behind Napoli or Paris Saint-Germain, who meet in Italy later on Tuesday, and face both those sides in their final two group games.
Here are the talking points from a raucous Rajko Mitic Stadium.
LIVERPOOL’S MISPLACED ARROGANCE
Jurgen Klopp in his team selection (the German made three changes with Daniel Sturridge, Adam Lallana and Joel Matip being brought into the side), the team selected and perhaps even the Liverpool supporters were misguided in their belief they could simply turn up and walk all over Red Star Belgrade.
To be honest, there has been this misplaced arrogance to Liverpool all season, a self-entitled attitude in which they expect to produce results without actually needing to perform.
They have gotten away with it through the early part of the campaign but in Serbia, Red Star finally delivered an ego check.
Talent alone isn’t always enough to secure victories because without the mental traits of desire and tenacity, sides of any quality will always have an opportunity to humble you.
And the hosts possessed plenty of fortitude and just enough ability in key moments to see off the wretched Reds.
Indeed, for just about every aspect of the game, Liverpool were atrocious. Even basic fundamentals like first touches and crosses were well below the standard expected of this group, pointing to mental deficiencies.
There was no urgency, no vibrancy and certainly no accuracy. The performances all round were so dire, it’s difficult to actually pinpoint any single perpetrator. Klopp when asked if he can put his finger on went wrong, replied: “I only have 10 fingers…”
Only Mohamed Salah with his enterprise can escape being chastised. Three straight Champions League defeats for the first time in the club’s history and just two attempts on target in their last two away assignments point to problems.
Last season’s finalist are in serious danger of going out in the group stages, and given the conceited attitude, they deserve to be.
That rousing victory over Paris Saint-Germain in the opening fixture seems a long time ago now.
Want to know which player’s reputation has swelled in recent weeks? Jordan Henderson.
Without even playing the injured Liverpool captain’s importance on this team has been made obvious.
After all, who would have guessed that a midfielder with great communication, urgency and the ability to change tempo with accurate short passing would be so critical?
If you’re wondering what exactly it is that Henderson does, then just observe the state of Liverpool’s midfield in Belgrade.
James Milner was rightly hailed for his excellent start to the season, but he’s been well below the levels displayed in the early months.
Georginio Wijnaldum has similarly dipped and the performance from the midfielders was a nadir, but one that isn’t all that surprising given their one-paced and limited displays of late.
This collapse of confidence has been building and the return of an energetic Henderson alongside Naby Keita is fast becoming a necessity.
If there is one statistic which best illustrates the middle men’s dire display, it’s the fact zero tackles were won from the trio of Wijnaldum, Milner and Adam Lallana in the first half.
Incidentally, we haven’t mentioned Lallana. A 30-year-old injury-prone midfielder who looks past his prime and hasn’t come close to replicating the form of two years ago is not exactly the quality squad option Klopp was talking about when it came to the discussion of claiming trophies.
A 65.7 per cent pass completion rate for Lallana says everything you need to know about how well he played in Belgrade.
TIME TO TALK ABOUT ALISSON
Liverpool paid an extortionate amount of money to sign Alisson from Roma and suffice to say, the Brazilian is not exactly living up to the glowing reputation he developed in Italy.
Indeed, Liverpool’s resolute rearguard, led by the tower of strength Virgil van Dijk, has kept his workload relatively simple so far. But in the last two fixtures, cracks have appeared.
Just because he is far better than Loris Karius and Simon Mignolet, doesn’t mean that he should escape examination or that more shouldn’t be expected.
Against Arsenal at the weekend, the 26-year-old was extremely fortunate when he wildly flew out of his goal and clattered Henrikh Mkhitaryan who could have either scored or earned a penalty when his header trickled just wide.
In Belgrade, he was erroneous for Milan Pavkov’s second. Yes, the strike was sweet but the ball was within reaching distance only for the stopper to dive to his right and stretch for the ball with his left hand.
Respected analyst and former goalkeeper David Preece even backed the assertion he should have done better with the effort. Alisson is far from alone in that regard, though.
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